Th17 Cells Research Articles

Histamine and Th2 cytokines independently and synergistically upregulate MMP12 expression in human M2 macrophages.

Beyond Th2 cells and various immune cells, M2 macrophages have been identified in lesional skin of atopic dermatitis (AD) indicating their involvement in the disease's underlying mechanisms. MMP12, a matrix-degrading enzyme, which is predominantly produced by macrophages, is increased in skin lesions of AD patients. In this study we investigated the expression of MMP12 mRNA in lesional AD skin at single cell level through RNA sequencing (scRNA-seq) and the expression of MMP12 in M2 macrophages from healthy individuals and AD patients in response to Th2 cytokines and histamine using quantitative PCR and ELISA. Additionally, we analyzed macrophages from dupilumab-treated AD patients using the same methods to assess the influence of Th2 cytokines on MMP12 expression ex-vivo. ScRNA-seq identified macrophages as the primary producers of MMP12 in lesional AD skin. In-vitro, both MMP12 mRNA and protein expression were significantly increased in monocytes during differentiation to M2 macrophages in the presence of histamine, of Th2 cytokines or of Th2 cytokines in combination with histamine. In M2 macrophages obtained from dupilumab-treated AD patients, the upregulation of MMP12 expression by IL-4 and IL-13 was attenuated. Our findings unveil a novel mechanism whereby Th2 cytokines and histamine regulate MMP12 expression, potentially impacting skin barrier homeostasis in AD.

Heat shock protein 70 promotes the progression of type 2 diabetic nephropathy by inhibiting T-cell immunoglobulin and mucin domain-3 and thereby promoting Th17/Treg imbalance.

Diabetic nephropathy (DN) is the most common complication of diabetes mellitus. We aimed to investigate the role of regulatory T cells (Tregs) and helper T cells 17 (Th17) in the development and progression of DN. A mouse type 2 diabetic nephropathy (T2DN) model was established. Immunohistochemistry was used to detect the expression of HSP70 and Tim-3 in mouse kidney tissues, and western blotting was used to detect the expression levels of HSP70 and Tim-3. PAS staining and Masson's trichrome staining were used to detect the degree of kidney injury. Flow cytometry was used to detect the number of Th17 and Treg cells in blood and kidney tissues. The expression levels of interleukin 17 (IL-17) and interleukin 10 (IL-10) in the serum were measured via ELISA. The expression of HSP70 was significantly increased while the expression of Tim-3 was significantly decreased in the kidneys of mice in the T2DN group compared with those in the control (NC) group. Additionally, the inhibition of HSP70 upregulated the expression of Tim-3 in T2DN mice. The Th17/Treg ratio was significantly greater in the blood and kidneys of the mice in the T2DN group than in those of the NC group, the expression of serum IL-17 was increased, and the expression of IL-10 was decreased. Increased HSP70 inhibits Tim-3 expression in T2DN mouse kidney tissues, and subsequently causes a Th17/Treg imbalance and an inflammatory response, ultimately leading to kidney injury. The inhibition of HSP70 may alleviate the progression of T2DN.

Efficacy of the cardiac glycoside digoxin as an adjunct to csDMARDs in rheumatoid arthritis patients: a randomized, double-blind, placebo-controlled trial.

Inflammation and angiogenesis are two main mechanisms that act as mutual pathways in rheumatoid arthritis (RA). This work aimed to study the efficacy of digoxin as an adjunct therapy to conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs) in active RA patients. In a randomized, double-blinded, placebo-controlled study, 60 adult patients with active RA received a placebo or digoxin (0.25mg every other day) combined with csDMARDs for 6months. The American College of Rheumatology (ACR) 20, ACR50, and ACR70 response rates and the disease activity score (DAS28) were assessed for patients. Flow cytometric analysis of Th17 cells and serum concentrations of IL-17A, IL-23, HIF-1α, and VEGF were evaluated before and after three and 6months of therapy. Following three and 6months of digoxin therapy combined with csDMARDs, significant differences were detected in laboratory and clinical parameters relative to the control group. After 6months, 83.3% of patients in the digoxin group, compared to 56.7% in the control group, achieved an ACR20 response (p = 0.024). The digoxin group had a significantly higher percentage of patients who achieved DAS28 remission after 6months (p = 0.024). Notable improvements in the Health Assessment Questionnaire Disability Index, ACR50, and ACR70 were detected in the digoxin group. Digoxin was well tolerated and exerted profound immunomodulatory and anti-inflammatory effects in RA patients, and may also exhibit anti-angiogenic properties, indicating that it might be an effective adjunct to csDMARDs in treating RA. clinicaltrials.gov, identifier NCT04834557.

Enhancing Th17 cells drainage through meningeal lymphatic vessels alleviate neuroinflammation after subarachnoid hemorrhage

BackgroundSubarachnoid hemorrhage (SAH) is a severe cerebrovascular disorder primarily caused by the rupture of aneurysm, which results in a high mortality rate and consequently imposes a significant burden on society. The occurrence of SAH initiates an immune response that further exacerbates brain damage. The acute inflammatory reaction subsequent to SAH plays a crucial role in determining the prognosis. Th17 cells, a subset of T cells, are related to the brain injury following SAH, and it is unclear how Th17 cells are cleared in the brain. Meningeal lymphatic vessels are a newly discovered intracranial fluid transport system that has been shown to drain large molecules and immune cells to deep cervical lymph nodes. There is limited understanding of the role of the meningeal lymphatic system in SAH. The objective of this research is to explore the impact and underlying mechanism of drainage Th17 cells by meningeal lymphatics on SAH.MethodsTreatments to manipulate meningeal lymphatic function and the CCR7-CCL21 pathway were administered, including laser ablation, injection of VEGF-C geneknockout, and protein injection. Mouse behavior was assessed using the balance beam experiment and the modified Garcia scoring system. Flow cytometry, enzyme-linked immunosorbent assays (ELISA), and immunofluorescence staining were used to study the impact of meningeal lymphatic on SAH drainage. Select patients with unruptured and ruptured aneurysms in our hospital as the control group and the SAH group, with 7 cases in each group. Peripheral blood and cerebrospinal fluid (CSF) samples were assessed by ELISA and flow cytometry.ResultsMice with SAH showed substantial behavioral abnormalities and brain damage in which immune cells accumulated in the brain. Laser ablation of the meningeal lymphatic system or knockout of the CCR7 gene leads to Th17 cell aggregation in the meninges, resulting in a decreased neurological function score and increased levels of inflammatory factors. Injection of VEGF-C or CCL21 protein promotes Th17 cell drainage to lymph nodes, an increased neurological function score, and decreased levels of inflammatory factors. Clinical blood and CSF results showed that inflammatory factors in SAH group were significantly increased. The number of Th17 cells in the SAH group was significantly higher than the control group. Clinical results confirmed Th17 cells aggravated the level of neuroinflammation after SAH.ConclusionThis study shows that improving the drainage of Th17 cells by meningeal lymphatics via the CCR7-CCL21 pathway can reduce brain damage and improve behavior in the SAH mouse model. This could lead to new treatment options for SAH.

RGS10 Deficiency Alleviated Intestinal Mucosal Inflammation Through Suppression of Th1/Th17 Cell Immune Responses in Ulcerative Colitis.

Regulator of G-protein signalling (RGS) 10 plays critical roles in several immune related diseases. However, whether RGS10 is involved in colonic inflammation of ulcerative colitis (UC) is still obscure. This study aimed to investigate the role of RGS10 in UC. In this study, RGS10 expression was examined by quantitative real-time polymerase chain reaction (qRT-PCR), western blotting, immunohistochemistry, and immunofluorescent analysis. Single-cell RNA sequencing of intestinal mucosa was performed to identify key immune cells with differentially expressed RGS10. RGS10 knockout mice were generated and established dextran sulphate sodium (DSS)-induced colitis. Expression of inflammatory cytokines on mRNA and protein levels was detected by qRT-PCR, enzyme-linked immunosorbent assay, and flow cytometry. We found that RGS10 expression was significantly elevated in UC patients, especially in CD4+ T cells, compared with healthy subjects. Intriguingly, RGS10 deficiency markedly alleviated DSS-induced colitis and decreased the proportion of Th1 and Th17 cells in lamina propria mononuclear cells (LPMCs), peripheral blood (PB), spleens, and mesenteric lymph nodes (mLNs). Mechanistically, RGS10 deficiency blocked the differentiation of Th1 and Th17 cells by inhibiting the phosphorylation of signal transducer and activator of transcription (STAT) 1 and STAT3. The co-immunoprecipitation analysis further showed that RGS10 could interact with protein tyrosine phosphatase non-receptor type 2 (PTPN2), and further regulated Th1 and Th17 cells differentiation of CD4+ T cells. In conclusion, RGS10 deficiency alleviated intestinal mucosal inflammation through inhibition of Th1/Th17 cell-mediated immune responses via interaction with PTPN2 in CD4+ T cells. Therefore, targeting RGS10 may represent a novel therapeutic approach for UC treatment.

DOCK8 deficiency due to a deep intronic variant in two kindreds with hyper-IgE syndrome

Dedicator of cytokinesis 8 (DOCK8) deficiency underlies the majority of cases of patients with autosomal recessive form of the hyper-immunoglobulin E syndrome (HIES). Most DOCK8 mutations involve deletions and splice junction mutations that abrogate protein expression. However, a few patients whose presentation is reminiscent of DOCK8 deficiency have no identifiable mutations. Using Whole Exome Sequencing (WES), we identified a deep intronic homozygous DOCK8 variant located in intron 36 (c.4626 + 76 A > G) in two unrelated patients with features of HIES that resulted in an in-frame 75 base pair intronic sequence insertion in DOCK8 cDNA, resulting in a premature stop codon (p.S1542ins6Ter). This variant resulted in variable decrease in DOCK8 expression that was associated with impaired T cell receptor-triggered actin polymerization, decreased IL-6-induced STAT3 phosphorylation, reduced expression of the Th17 cell markers CCR6 and IL-17, and higher frequencies of GATA3+ T cells indicative of Th2 skewing. Our approach extends the reach of WES in identifying disease-related intronic variants. It highlights the role of non-coding mutations in immunodeficiency disorders, including DOCK8 deficiency, and emphasizes the need to explore these mutations in unexplained inborn errors of immunity.

Virus-specific Th17 Cells Are Induced by Human Cytomegalovirus after Renal Transplantation.

CMV infection and Th17 cells are independently associated with increased risk for late allograft loss after renal transplantation. Although CMV-specific Th17 cells are detectable in animal models and nontransplant clinical populations, evidence linking CMV and Th17 cells after renal transplantation remains unclear. This prospective observational study evaluated a cohort of renal transplant recipients during 12 mo posttransplant to assess the presence of CMV-specific Th17 cells in peripheral blood and their relationship to pretransplant CMV serostatus and CMV DNAemia. CMV-specific Th17 cells were identified among CMV serostatus donor (D)+ and/or recipient (R)+ recipients and expanded during both primary (D+/R-) and reactivated (D+/R+, D-/R+) CMV DNAemia. A subset of CMV-specific Th17 cells coexpressed IFN-γ, indicating a Th1/17 phenotype. These Th17 and Th1/17 cells expressed CCR6, CCR5, activation and terminal differentiation markers (CD95, OX40, HLA-DR, CD57), and a central/effector memory phenotype. CMV-specific Th1/17 cells expressed activating/inhibitory receptors (CD57, 4-1BB, CD160, CTLA-4, PD-1) at higher frequencies than Th17 cells. In contrast, staphylococcal enterotoxin B-induced Th17 cells did not expand during CMV DNAemia, did not differ between CMV serostatus groups over time, expressed CCR6, predominantly coexpressed TNF-α, and had lower expression of activating and inhibitory receptors than pp65-specific Th17 and Th1/17 cells. These data show that CMV-specific Th17 cells expand during episodes of CMV DNAemia among renal transplant recipients, and that these virus-specific Th17 and Th1/17 cells have distinct phenotypes from global circulating Th(1)/17 cells. These results suggest a potential proinflammatory pathway by which CMV-induced Th17 cells may contribute to allograft injury, increasing risk for late allograft loss.

Restriction of innate Tγδ17 cell plasticity by an AP-1 regulatory axis.

IL-17-producing γδ T (Tγδ17) cells are innate-like mediators of intestinal barrier immunity. While Th17 cell and ILC3 plasticity have been extensively studied, the mechanisms governing Tγδ17 cell effector flexibility remain undefined. Here, we combined type 3 fate-mapping with single cell ATAC/RNA-seq multiome profiling to define the cellular features and regulatory networks underlying Tγδ17 cell plasticity. During homeostasis, Tγδ17 cell effector identity was stable across tissues, including for intestinal T-bet + Tγδ17 cells that restrained IFNγ production. However, S. typhimurium infection induced intestinal Vγ6 + Tγδ17 cell conversion into type 1 effectors, with loss of IL-17A production and partial RORγt downregulation. Multiome analysis revealed a trajectory along Vγ6 + Tγδ17 effector conversion, with TIM-3 marking ex-Tγδ17 cells with enhanced type 1 functionality. Lastly, we characterized and validated a critical AP-1 regulatory axis centered around JunB and Fosl2 that controls Vγ6 + Tγδ17 cell plasticity by stabilizing type 3 identity and restricting type 1 effector conversion.

Effect and mechanism of allergen-specific immunotherapy on small airway dysfunction in children with asthma.

The purpose of this study was to investigate the effectiveness of allergen-specific immunotherapy (AIT) on small airway dysfunction (SAD) and the underlying mechanism with a special focus on basophils. Sixty-five children with mild to moderate asthma who were under regular inhaled corticosteroid (ICS) treatment for more than 1 year but whose FEF75 remained below 65% of the predicted value and had positive results for serum Der p or Der f were enrolled. Children with asthma underwent house dust mite (HDM) subcutaneous immunotherapy (SCIT) treatment for 1 year. Clinical symptoms and lung function were evaluated every 3 months during HDM SCIT treatment. Basophil activation test (BAT) was carried out before and after HDM SCIT treatment. RNA sequencing was performed in isolated basophils from peripheral blood after 6 months of HDM SCIT treatment, followed by GO term and KEGG pathway enrichment analysis between patients with and without HDM SCIT treatment. HDM AIT treatment ameliorated clinical symptoms while concurrently improved lung function parameters, such as FEV1/FVC, FEF75, FEF50 and MMEF (p < .05). It is worth noting that FEF75 values showed a highly significant, gradual and persistent increase (from 49.55 ± 1.27% at baseline to 71.89 ± 2.64% after 1 year of therapy) and 22 of 35 patients no longer had SAD after 1 year of treatment. BAT results revealed that AIT treatment significantly reduced basophil activity to the inhalant allergen mixtures containing HDM in vitro challenge from baseline. GO term and KEGG pathway enrichment analysis of basophils revealed that downregulated genes were mainly involved in immune cell activation, antigen presentation, and Th2 cell differentiation. Our study demonstrated that HDM AIT not only improved SAD related lung function parameters, but also reduced basophil activity. RNA sequencing revealed the inhibition of phagocytosis and the phagosome pathway in basophils which may affect the polarization of Th2 cell differentiation after HDM AIT.

Mechanism of biliary atresia caused by T follicular helper cells-induced immune injury

BackgroundBiliary atresia (BA) has diverse and unclear pathogenesis, which may be related to immune response in response to a foreign stimulus. T follicular helper (Tfh) cells have been found to play an important role in various immune diseases.AimsTo investigate the expression of Tfh cells in BA and non-BA cholestatic diseases in children.MethodsTranscriptome sequencing and Gene Ontology (GO) enrichment analysis were performed to investigate the differences in gene expression between the BA group and the non-BA cholestasis group. Study the distribution of Tfh cells in liver tissues of the BA and non-BA cholestatic groups through single sample gene set enrichment analysis (ssGSEA). Tfh cells (CD3+Bcl6+) in liver tissues from BA patients were labeled by double immunofluorescent staining to verify their distribution in the liver.ResultsTranscriptome sequencing showed differences in gene expression between the BA group and the non-BA cholestasis group. A total of 808 genes were up-regulated and 405 genes were down-regulated in BA, suggesting that there might be a specific immune response in BA. GO enrichment analysis showed that BA group had augmented response to foreign stimulus and increased metabolic process compared to the non-BA cholestatic group. The relative proportion of immune cells was analyzed by ssGSEA method. The proportions of Tfh cells, activated B cells, CD4+ T cells, memory B cells and Th2 cells were higher in the BA group than in the non-BA cholestatic group. Fluorescence immunostaining showed that Tfh cells were significantly increased in liver tissue samples of the BA group compared to the non-BA cholestasis group, which was consistent with the transcriptome sequencing results.ConclusionTfh cells share in immune cascade involvement in BA. Our work support immune pathogenesis of the in response to a stimulus that might be foreign in BA.

MINCLE and TLR9 agonists synergize to induce Th1/Th17 vaccine memory and mucosal recall in mice and non-human primates

Development of new vaccines tailored for difficult-to-target diseases is hampered by a lack of diverse adjuvants for human use, and none of the currently available adjuvants induce Th17 cells. Here, we develop a liposomal adjuvant, CAF®10b, that incorporates Mincle and Toll-like receptor 9 agonists. In parallel mouse and non-human primate studies comparing to CAF® adjuvants already in clinical trials, we report species-specific effects of adjuvant composition on the quality and magnitude of the responses. When combined with antigen, CAF®10b induces Th1 and Th17 responses and protection against a pulmonary infection with Mycobacterium tuberculosis in mice. In non-human primates, CAF®10b induces higher Th1 responses and robust Th17 responses detectable after six months, and systemic and pulmonary Th1 and Th17 recall responses, in a sterile model of local recall. Overall, CAF®10b drives robust memory antibody, Th1 and Th17 vaccine-responses via a non-mucosal immunization route across both rodent and primate species.

High-CBD Extract (CBD-X) in Asthma Management: Reducing Th2-Driven Cytokine Secretion and Neutrophil/Eosinophil Activity.

Asthma is a chronic inflammatory disorder of the airways affecting over 10% of the global population. It is characterized by airway inflammation, mucus hypersecretion, and bronchial hyperresponsiveness, driven predominantly by type 2 helper T cells (Th2) and type 2 innate lymphoid cells (ILC2s) in a subset of patients. However, a significant portion of asthmatic individuals present with "type 2-low" asthma that is often refractory to standard inhaled corticosteroid (ICS) therapy. Therefore, developing innovative therapeutic strategies has become essential. Recent studies have highlighted cannabidiol (CBD) as a promising anti-inflammatory agent capable of modulating immune responses. This study investigates the therapeutic potential of a high-CBD extract (CBD-X) in asthma. We evaluated the effects of CBD-X on cells involved in asthma pathogenesis using primary human Th2 cells, neutrophils, and asthma mouse model. Our findings indicate that CBD-X extract inhibits Th2 differentiation and reduces the secretion of IL-5 and IL-13, which are crucial cytokines in asthma. Additionally, CBD-X significantly reduces pro-inflammatory cytokines IL-8 and IL-6 in neutrophils and impairs their migration, a critical step in airway inflammation. In a murine asthma model, CBD-X administration led to marked downregulation of IgE and pro-asthmatic cytokines, along with reduced leukocyte, eosinophil, and neutrophil infiltration in lung tissues. These results suggest that CBD-X extract could offer a novel and complementary approach to managing both type 2-high and type 2-low asthma by targeting key inflammatory pathways and modulating immune cell behavior.

The Use of a REV-ERB Synthetic Agonist for T Helper 17-Based Cancer Therapy

Researchers have titled chronic inflammation the “hallmark of cancer,” due to its key role in inducing nearly twenty percent of the malignancies worldwide. Chronic inflammation exists for an extended period, gradually creating the right enviroment in which cancer can thrive. Chronic inflammation causes damage to cell DNA and alters the way cells replicate and divide; this damages healthy tissue and promotes cancerous tumor growth. T Helper 17 (Th17) cells are a subset of T cells known to play a key role in driving inflammation. Th17 cells tend to accumulate within the tumor microenvironment. While their role in tumorigenesis is complex, they promote tumor growth in many cancer types. REV-ERBs are a class of nuclear hormone receptors that was recently identified as a modulator of Th17 cell development. This experiment demonstrates that the use of a REV-ERB agonist reduces inflammation through the Th17 molecular network. We used qPCR to test the effects of a REV-ERB agonist on the relative expression of genes associated with Th17 cell differentiation and resulting inflammation. We used samples of mouse microglial cells (BV2 cells) cultured in a variety of conditions. When cultured in the presence of lipopolysaccharides (LPS), bacterial toxins, BV2 cells undergo an inflammatory response. The BV2 cells co-treated with LPS and a REV-ERB agonist expressed these genes (Il-10, Il-1β, Il-6, Ccl2, Cox-2, Tnfα) to a lesser extent than the BV2 cells treated with LPS alone; thus, the REV-ERB agonist counteracted the effect of the LPS. These results indicate that REV-ERB agonists are worthy of future research into their utility as a means of cancer prevention and treatment.

MiR-27a inhibits the growth and metastasis of multiple myeloma through regulating Th17/Treg balance.

The imbalance between T helper 17 (Th17) and T regulatory (Treg) cells plays a key role in the progression of multiple myeloma (MM). The gene expression profiles of MM were acquired and examined from the Gene Expression Omnibus (GEO) database (GSE72213). Our research involved experimental investigations conducted using the MOPC-MM mouse model. Dysregulation of Treg and Th17 cells was evaluated through flow cytometry, while the levels of inflammatory factors were measured using the enzyme-linked immunosorbent assay. Cell proliferation was gauged using the Cell Counting Kit-8 assay, and cell apoptosis was quantified via flow cytometry. Cell metastasis capabilities were determined by conducting transwell assays. To confirm the relationship between miR-27a and PI3K, a dual-luciferase reporter assay was employed. Finally, proteins associated with the PI3K/AKT/mTOR signaling pathway were assessed using western blotting. MiR-27a exhibited reduced expression levels in MM. Moreover, it exerted control over the equilibrium of Th17 and Treg cells while reducing the expression of inflammatory mediators such as TGF-β1 and IL-10 in an in vivo setting. Elevated miR-27a levels led to the inhibition of cell viability, colony formation capacity, migratory and invasive traits in an in vitro context. The PI3K/AKT/mTOR signaling pathway was identified as a direct target of miR-27a and could reverse the effects induced by miR-27a in MM cells. Notably, PI3K was directly targeted by miR-27a. Our study revealed that miR-27a inhibited MM evolution by regulating the Th17/Treg balance. Inhibition of the PI3K/AKT/mTOR signaling pathway by miR-27a may play a potential mechanistic role.

Circulating Baseline CXCR3+Th2 and Th17 Cell Proportions Correlate With Trabecular Bone Loss After 48 Weeks of Biological Treatment in Early Rheumatoid Arthritis.

The high prevalence of osteoporosis in rheumatoid arthritis (RA) is due to inflammation that stimulates differentiation of osteoclasts, a process involving circulating monocytes and T cell-derived factors. The aim of this study was to evaluate relations between circulating monocytes, T cell subsets, and changes in bone characteristics before and after treatment with biological disease-modifying antirheumatic drugs (bDMARDs) in RA. Thirty patients with untreated early RA who met the American College of Rheumatology/EULAR 2010 criteria were included. Data were collected before and 48 weeks after treatment with methotrexate (MTX) together with one of three bDMARDs (abatacept, tocilizumab, or certolizumab pegol). Disease activity was measured using the Clinical Disease Activity Index, swollen or tender joint counts, C-reactive protein levels, and erythrocyte sedimentation rates. Proportions of monocyte and CD4+ T cell subsets in blood samples were analyzed by flow cytometry. Bone densitometry was performed using high-resolution peripheral quantitative computed tomography (HR-pQCT). HR-pQCT revealed an overall decrease in cortical (P = 0.009) and trabecular (P = 0.034) bone mineral density, although a subset of patients showed no bone loss after 48 weeks of treatment. The overall bone loss was not associated with age, body mass index, sex, intraarticular glucocorticoid injections, or baseline disease activity. Loss of trabecular bone volume fraction correlated with high proportions of circulating CXCR3+Th2 cells (r = -0.38, P = 0.04) and CXCR3+Th17 cells (r = -0.36, P = 0.05) at baseline. Similarly, no loss of trabecular bone volume fraction correlated with high proportions of regulatory T cells (r = 0.4, P = 0.03) at baseline. However, the associations were not significant when corrected for confounders and multiple testing. MTX together with bDMARDs efficiently reduce disease activity but only prevent bone loss in a subset of patients with RA after 48 weeks of treatment. The correlations of circulating baseline T helper cell and regulatory T cell populations with trabecular bone changes suggest a potential novel role for these cells in systemic bone homeostasis during early RA.

Transient High Salt Intake Promotes T-Cell-Mediated Hypertensive Vascular Injury.

Dietary high salt (HS) intake has a strong impact on cardiovascular diseases. Here, we investigated the link between HS-aggravated immune responses and the development of hypertensive vascular disease. ApolipoproteinE-deficient mice were transiently treated with HS (1% NaCl) via drinking water for 2 weeks, followed by a washout period, and subsequent Ang II (angiotensin II) infusion (1000 ng/kg per min for 10 days) to induce abdominal aortic aneurysms/dissections and inflammation. While transient HS intake alone triggered nonpathologic infiltration of activated T cells into the aorta, subsequent Ang II infusion increased mortality and the incidence of abdominal aortic aneurysms/dissections and atherosclerosis compared with hypertensive control mice. There were no differences in blood pressure between both groups. In transient HS-treated hypertensive mice, the aortic injury was associated with increased inflammation, accumulation of neutrophils, monocytes, CD69+CD4+ T cells, as well as CD4+ and CD8+ memory T cells. Mechanistically, transient HS intake increased expression levels of aortic RORγt as well as splenic CD4+TH17 and CD8+TC1 T cells in Ang II-treated mice. Isolated aortas of untreated mice were incubated with supernatants of TH17, TH1, or TC1 cells polarized in vitro under HS or normal conditions which revealed that secreted factors of HS-differentiated TH17 and TC1 cells, but not TH1 cells accelerated endothelial dysfunction. Our data suggest that transient HS intake induces a subclinical T-cell-mediated aortic immune response, which is enhanced by Ang II. We propose a 2-hit model, in which HS acts as a predisposing factor to enhance hypertension-induced TH17 and TC1 polarization and aortic disease.

Build muscles and protect myelin

Abstract Multiple sclerosis (MS) is a chronic and debilitating autoimmune disease of the central nervous system (CNS) in which a CNS-driven immune response destroys myelin, leading to wide range of symptoms including numbness and tingling, vision problems, mobility impairment, etc. Oligodendrocytes are the myelinating cells in the CNS, which are generated from oligodendroglial progenitor cells (OPCs) via differentiation. However, for multiple reasons, OPCs fail to differentiate to oligodendrocytes in MS and as a result, stimulating the differentiation of OPCs to oligodendrocytes is considered beneficial for MS. The β-hydroxy β-methylbutyrate (HMB) is a widely-used muscle-building supplement in human and recently it has been shown that low-dose HMB is capable of stimulating the differentiation of cultured OPCs to oligodendrocytes for remyelination. Moreover, other causes of autoimmune demyelination are the decrease and/or suppression of Foxp3-expressing anti-autoimmune regulatory T cells (Tregs) and upregulation of autoimmune T-helper 1(Th1) and Th17 cells. Experimental autoimmune encephalomyelitis (EAE) is an animal model of MS in which the autoimmune demyelination is nicely visible. It has been reported that in EAE mice, oral HMB upregulates Tregs and decreases Th1 and Th17 responses, leading to remyelination in the CNS. Here, we analyze these newly-described features of HMB, highlighting the putative promyelinating nature of this supplement.

Association of aging related genes and immune microenvironment with major depressive disorder

ObjectiveTo study the relationship between aging related genes (ARGs) and Major Depressive Disorder (MDD). MethodsThe datasets GSE98793, GSE52790 and GSE39653 for MDD were obtained from the GEO database, and ARGs were obtained from the Human Aging Genome Resources database. Differential expression genes (DEGs) screening and GO, KEGG enrichment analysis were performed to uncover the underlying mechanisms. To identify key ARGs associated with MDD (key ARG-DEGs), we employed machine learning methods such as LASSO, SVM, and Random Forest, as well as the plug-ins CytoHubba-MCC and MCODE methods. SsGSEA was used to analyze the immune infiltration of MDD and healthy controls. Furthermore, we created risk prediction nomograms model and ROC curves to assess not only the ability of key ARG-DEGs to diagnose MDD, but also predicted miRNAs and transcription factors (TFs) that might interact. Finally, a two-sample Mendelian randomization (MR) study was performed to confirm the association of identified key ARG-DEGs with depression. ResultsDEGs of ARGs between MDD and healthy controls led to the identification of eight ARG-DEGs. GO and KEGG analysis revealed that the pathways associated with these eight ARG-DEGs were primarily concentrated in Foxo pathway, JAK-STAT pathway, Pl3K-AKT pathway, and metabolic diseases. A comprehensive analysis further narrowed down the 8 ARG-DEGs to 4 key ARG-DEGs: MMP9, IL7R, S100B, and EGF. Immune infiltration analysis indicated significant differences in CD8(+) T cells, macrophages, neutrophils, Th2 cells, and TIL cells between MDD and control groups, correlating with these four key ARG-DEGs. Based on these four key ARG-DEGs, a risk prediction model for MDD was developed. The miRNA-TF-mRNA interaction network of the key ARG-DEGs highlights the complexity of the regulatory process, providing valuable insights for future related research. The MR study suggested a potential causal relationship between MMP9 and the risk of depression. ConclusionThe process of aging, immune dysregulation, and MDD are closely interconnected. MMP9, IL7R, S100B, and EGF may be used as novel diagnostic biomarkers and potential therapeutic targets for MDD, especially MMP9.

Neuropeptide signalling orchestrates T cell differentiation.

The balance between T helper type 1 (TH1) cells and other TH cells is critical for antiviral and anti-tumour responses1-3, but how this balance is achieved remains poorly understood. Here we dissected the dynamic regulation of TH1 cell differentiation during in vitro polarization, and during in vivo differentiation after acute viral infection. We identified regulators modulating T helper cell differentiation using a unique TH1-TH2 cell dichotomous culture system and systematically validated their regulatory functions through multiple in vitro and in vivo CRISPR screens. We found that RAMP3, a component of the receptor for the neuropeptide CGRP (calcitonin gene-related peptide), has a cell-intrinsic role in TH1 cell fate determination. Extracellular CGRP signalling through the receptor RAMP3-CALCRL restricted the differentiation of TH2 cells, but promoted TH1 cell differentiation through the activation of downstream cAMP response element-binding protein (CREB) and activating transcription factor 3 (ATF3). ATF3 promoted TH1 cell differentiation by inducing the expression of Stat1, a key regulator of TH1 cell differentiation. After viral infection, an interaction between CGRP produced by neurons and RAMP3 expressed on T cells enhanced the anti-viral IFNγ-producing TH1 and CD8+ T cell response, and timely control of acute viral infection. Our research identifies a neuroimmune circuit in which neurons participate in T cell fate determination by producing the neuropeptide CGRP during acute viral infection, which acts on RAMP3-expressing T cells to induce an effective anti-viral TH1 cell response.

Bergapten attenuates sepsis-induced acute lung injury in mice by regulating Th17/Treg balance

Background The abnormality of the immune system caused by infection is a contributor to the organ dysfunctions associated with sepsis. The balance between Th17/Treg cells is essential for maintaining immune homeostasis. Bergapten is a natural furocoumarin and has been reported to alleviate the Th17/Treg imbalance. Here, we explored the effects of bergapten on the inflammation and immune state in mouse models of sepsis. Methods The model was established using the cecal ligation and puncture method. Mice were administered 30 mg/kg bergapten. Histological examination, RT-qPCR, enzyme-linked immunosorbent assay, immunoblotting, immunofluorescence, immunohistochemistry, and flow cytometry were used to evaluate the effects of bergapten in vivo. Results Bergapten ameliorated lung damage, reduced lung wet/dry weight ratio, inhibited myeloperoxidase activity, and reduced inflammatory cell infiltration. Bergapten also restrained sepsis-induced inflammation via inhibition of inflammatory cytokines and NF-κB signaling. These effects were accompanied by the restored Th17/Treg balance induced by bergapten. Bergapten decreased the number of Th17 cells and elevated the number of Tregs, and this effect was mediated by the signal transducer and activator of transcription 5 (STAT5)/Forkhead box P3 (Foxp3) and STAT3/retinoid-related orphan receptor-γt (RORγt) pathways. Conclusions Bergapten exerted anti-inflammatory effects in acute lung injury by improving the Th17/Treg balance, which suggested a potential of bergapten as an immunomodulatory drug treating sepsis-associated diseases.